[Drax]

advantages - very hard hitting characters, cheap troops, fear causing, at present your army can increase in size during the battle - in the new book, you can't increase the size beyond the original for any troops other than zombies
disadvantages - magic reliant, troops are weak and for the most part lightly armoured, slow, take excess wounds if they lose a combat and are all but destroyed if the general dies.

the new book is out march 8th and gw stores have a 'staff copy' now which usually they will let you look at if you pre-order the book.

as for whether they are newb friendly army, they have there good points for a newb - such as your enemy's army will gradually dwindle down whereas yours wont (if you are lucky) but on the flipside you are going to need to learn the magic rules straight away - something that can normally be avoided initially unless you play Tomb Kings or Tzeentch Chaos.

i would say that as well as my main army, the counts were my first army, and i got my head around them fairly early on, so you should be ok.

as for 'compared to other armies', its the same as 40k - get the balance right and you could slaughter any opposition, but be prepared to take a few losses initially.